US2882196A - Pesticidal compositions - Google Patents

Description

States Patent COMPOSITIONS No Drawing. Application August 22, 1956 Serial No. 605,471

3 Claims. 01. 1 7-22 The present invention relates to pesticidal compositions and is particularly concerned with novel compositions including as active toxic ingredients 0,0-diethyl S-ethylthiomethyl phosphorodithioate and a trichloromethyl benaenethiosulfonate compound.

' 0,0 diethyl S ethylthiomethyl phosphorodithioate (commonly identified as Thimet) has recently come into wide usage as an agricultural insecticidal toxicant. This compound when applied on or in proximity to seeds will protect the developing seedlings and young plants from attack by pests such as aphids, beetles, thrips, leaf hoppers, mites and the like. This unique action is brought about by absorption and translocation of the compound through the plant sap to all growing parts of the plant. In such use, the actionof the compound has been established as being relatively specific with little or no control being accomplished of parasitic fungi which may cause a reduced number of seedlings to emerge and develop in the planted areas.

In accordance with the present invention, it has been found that a trichloromethyl benzenethiosulfonate compound of the formula x-Qsm-socn wherein X represents C1 or CH may be combined with 0,0-diethyl S-ethylthiomethyl phosphorodithioate to obtain pesticidal compositions having very desirable properties for the control of insects and fungus organisms. In such mixtures there appears to be no chemical incompatibility between the toxic constituents, and the toxicants appear to be mutually activated so that a greater than additive eifect is accomplished in controlling pests and particularly in regard to establishing an increased stand of healthy vigorous plants.

The new'toxicant mixtures may be utilized with an inert material as a carrier, for example water, an organic solvent, a finely divided solid, a wetting and dispersing agent, an aqueous emulsion, or any suitable combination of these.

In operating in accordance with this invention any suitable'amount of the trichloromethyl benzenethiosulfonate compound may be employed in combination with 0,0- diethyl S-ethylthiomethyl phosphorodithioate to obtain compositions in which the toxicants are mutually activating. The exact amount of either toxicant in any one combination is capable of considerable variation. In general, from one to 30 parts by weight of the trichloromethyl benzenethiosulfonate compound is utilized with each 30 parts of 0,0-diethyl S-ethylthiomethyl phosphorodithioate.

More important considerations in determining the preferred proportions are the type of composition in which the mixture of toxicants is to be applied, and the period for which residual control is required. For example, in seed applications, good results are obtained with compositions'containing from about 20 to about 60% by weight of a mixture of toxicants within the above-noted "ice ratios. When dusts are applied to the soil, particularly as furrow applications, the mixture of toxicants may constitute from about one to about 10% of the weight of the final composition. In spray applications, the toxicant mixture is usually applied in the range of from about one to about 20 pounds per. acre, and preferably in the range of from 3 to 8 pounds per acre.

In the preparation of dusts, the mixture of toxicants may be mixed with the finely divided carrier in any conventional manner. Operable carriers include clays, talc, wood flour, activated carbon, silica, chalk and the like.

When a concentrate is prepared, the mixture of toxi cants is ground or otherwise dispersed with wetting or dispersing agents to provide products adapted to be dis persed in water or other aqueous spray compositions, The toxicants may also be separately compounded in concentrate form and mixed together upon dilution in the spray tank. Suitable wetting and dispersing agents include sodium lauryl sulfate, isopropylnaphthalene so'di um sulfonate (Aerosol 0S), dioctyl sodium sulfojsuccinate (Aerosol OT), alkylated aryl polyether alcohol (Triton X100), modified phthalic glycerol alkyd resin (Triton B1956), and the salts of alkyl andaryl sulfonic acids (Daxad 21). 'Suitable sticking agents, which may be employed in compositions applied to seeds, include gelav tins, methylcellulose, soluble casein and spindle oil.

The following examples, in which parts are by weight, are illustrative of the invention.

EXAMPLEI In order to show the unexpectedly beneficial effect ob-' tainable in treating seeds in accordance with this inven tion, several treating compositions were prepared.

A dust was prepared by grinding and mixing together 44 parts of 0,0-diethyl S-ethylthiomethyl phoph'orodi thioate, 5 parts of trichloromethyl p-chlorobenzenethio-' sulfonate, 2 parts of methylcellulose, and 49 parts of activated carbon (Nuchar C115N). This composition was labeled Dust A.

Similarly, a dust was prepared containing 5 parts of trichloromethyl p-chlorobenzenethiosulfonate, 2 parts of methylcellulose and 93 parts of activated carbon. This composition was labeled Dust B.

A third dust was prepared in the same manner. It contained 44 parts of 0,0-diethyl S-ethylthiomethyl phosphorodithioate, 2 parts of methylcellulose and 54 parts of activated carbon. This composition was labeled Dust C.

Each composition was applied to'cotton seeds (variety Deltapine 15) in the proportion of 8 parts of dust per 100 parts of seed. A rotating drum type seed treater was used' to obtain uniform distribution of the compositions on the seed, and 2% water, based on seed weight, was added to obtain good coating and adherence.

The treated seeds were planted in soil of good fertility in a greenhouse held at approximately F., using duplicate flats of 50 seeds each. Table I gives the percent emergence or stand of seedlings from each treatment, counts being made twenty-one days after planting.

His readily apparent that Dust A produced a much better result than would have been expected from the use' of either Dust B or C alone.

1 EXAMPLEII- Example I was repeated using cotton seed (variety' 7 Coker wilt), and with the temperature of the green- ,Tdble .11 Bust: Percentstand ofcotton seedlings PA .68 B 29 1C 8 Fourweeks after planting, cottonplants'which had {developed from tseejd treated with'Dusts A, l3 andC were infested with two=spotted spider mites (Tetranychus .bimacrg'latus). "The infested plants were examined three days'later, and theppercent kill of mites was recorded as follows:

Table "III Percent-kill ofr-rnites 100 It canbe seen that I'Dust A was outstanding in establishinga strong vigorous stand of cotton plants, and in keeping the developing plants free of. attack by mites.

EXAMPLE IV A dust was prepared by mixin together 44 parts of 0,0-diethyl S-ethylthiomethyl phosphorodithioate, 10 outs of trichloremethy ;r1 mc hylbenzenethiosultenatc, 2 of methyleelll-lloae 44 parts of activated carbon (Nuchar-C1115N) composition waslabeled Dust .D.

fiimila ly, d st prepar d ontaining 1 m f triehloromethyl .pamethylbenzenethiosulfonate, 2 parts of methylcellulose and :88 nartsot a ti ated carbon. eomposition' asilab led Dust E.

third dust wasprepared'in the samemanner. It contained 44 parts of 0,0-diethyl S-ethylthiomethyl phosphorodithioate, 2 parts of methylcellulose and 54 parts of activated carbon. Ihis'eomposition was labeled Dust .5.

.Each composition was :applied to cotton seeds (variety Deltapine 15) in the proportion of 4 parts of dust per 50 parts of seed. The treated seeds were planted in soil of good fertility in a greenhouse held at approximately 80 -F,, using duplicate flats of 50 seeds each. Table IV gives "the percent stand .of seedlings from each treatment,;counts :being made twenty-one days after plant- 1118- .Table IV Dust: '*Pe rcent stand of cotton seedlings D 90 E 40 *F l '22 EXAMPLE V Example IV was repeated with the temperature of the greenhouse being'held at approximately 65 F. TableV gives the percent stand of seedlings from each treatment.

Four weeks after planting, cottonplants which had develope rom seed tr ated with Duets D, E and F wer 4 infested with two-spotted spider mites. "Hie plants were examined three dayslater, and the kill of mites was recorded as follows:

Table VI Dust: Percent kill of mites D 100 E 0 F 100 EXAMPLE VII Dusts D, B and'F were applied to pea seeds (variety Perfection) in the proportion .of' one part ofrdustgper 50 parts of seed. The "treated seeds-were planted in soil of good fertility in a greenhouse held at approximately F., using duplicate flats of "50 seeds each. Table VII gives the percent stand of seedlings from each treatment, counts being made twenty-one days after planting.

Table VI] Dust: Percen stan nines-mi itia H v 26 *F EXAMP E VIII Example V11 was repeated .with the 'temperatureofthe greenhouse being held at approximately 65" FF. Table 'VlIIgives-the pereentrstandnt seedlings fromeacb treatment.

Table VIII Dust: rsen t-peeseeflltnlfi :nxAMrLE'nr Four weeks after planting, plants whiphlhafl developed from pea seed treated with Dusts 1), E and F were infested with aphids. The infested plants were examined three days later, and the percent kill-of aphids was recorded as follows:

Table JIX Dust: P en k ll o ap ids D 103 E *0 F V 19 W -cla m:

1 .A pesticidal composition comprising as active-tonic ingredients from about one to about :30'parts @bysveight of a .trichloromethyl benzenethiosulfonate compound '"of th formu XQSOg-S-O'Gh wherein ;X rep sen s a memb r of the group ensist ne eff :Cl and-EH3, fer-each .301 or =Q,O- i hs"l :S flthflthiqmethyl ph p o o thio te- ;3- A =pe t cida1 co p it on mp i n an inert ca ier and d spersed th rein as c e oxi ingredients 5 from about one to about 30 parts by weight of a tri- References Cited in the file of this patent chloromethyl benzenethiosulfonate compound of the for- FOREIGN PATENTS mula 1,099,722 France Mar. 2a, 1955 G OTHER REFERENCES Wadley: The evidence Required to Show Synergistic wherein X represents a member of the group consisting Action of Insecticides and a Short Cut in Analysis, of Cl and CH for each 30 parts of 0,0-diethy1 S-ethyl- U.S.D.A., June 1945 (ET-223), pp. 1-7. thiomethyl phosphorodithioate. J our. Econ. Ent., vol. 50, No. 2, p. 226.

Claims (1)

1. A PESTICIDAL COMPOSITION COMPRISING AS ACTIVE TOXIC INGREDIENTS FROM ABOUT ONE TO ABOUT 30 PARTS BY WEIGHT OF A TRICHLOROMETHYL BENZENETHIOSULFONATE COMPOUND OF THE FORMULA